By Marc Weller
Lecturer in International Law at the Centre of International Studies,
University of Cambridge

Amid signs military action against Iraq could be on the cards BBC News Online examines the legal implications

Traditional international law imposes strict limitations on the use of
force by states.

Military measures may only be taken under a mandate of the UN Security Council, in self-defence or in the very limited circumstances of an overwhelming humanitarian emergency.

The law of self-defence, however, does not permit the use of force against speculative threats that might emerge in the future

Neither of the three possible
justifications applies to the proposed armed action to dislodge the regime
of Saddam Hussein from Iraq.

The Security Council has adopted numerous resolutions and decisions
condemning Iraq's failure to comply with the obligation to grant full
access to international arms inspectors and to cooperate with them in good faith.

However, the Council has not gone as far as authorising military
enforcement action to ensure compliance.

Dubious legacy

Individual states cannot arrogate
to themselves the power to act where the Council itself has been unwilling to take action.

Hence, operation Desert Fox, the 72-hour bombardment of
Iraq by the US and UK of December 1998, was not covered by UN authority.

The ongoing military skirmishes in the skies above Iraq since then are also
of dubious legality.

Tony Benn is warning against war with Iraq

The next possible argument is self-defence.

It has been asserted that Iraq
must be prevented from rebuilding its conventional, and possibly also its
unconventional, forces so as to prevent a future threat to the states of the region.

Flexible claims

Baghdad, after all, has already launched two aggressive wars,
against Iran and against Kuwait respectively.

Preventative action, it is asserted, is the only means of ensuring that no further attack can be launched.

The law of self-defence, however, does not permit the use of force against speculative threats that might emerge in the future.

If Iraq had deployed its military forces in an offensive posture, under order and ready to strike its neighbours, a case for anticipatory self-defence might be made.

But this is not the case at present.
Given the dangers that could emanate from biological or chemical weapons, the US and UK have instead argued that a more flexible standard has to be
applied.

Heavy burden of proof

Once such weapons are used, it is too late to mount an effective
defence.

Hence, they have to be countered before they can be deployed
successfully.

Even if this argument were to be accepted, this would place a
heavy burden of proof on the US administration to demonstrate that Iraq has both the capacity and the intent to use such weapons, and is ready to do so without warning.

The context of US President Bush's war on terror also does not provide a
legal justification in itself.

The unilateral act of the US of "declaring war" against an open ended number of states-at any rate not meant as a technical declaration of war in the classical sense-does not render the subsequent use of force against states so nominated lawful.

Punitive strikes forbidden

Air strikes would only be permissible if there is clear evidence that the Iraqi government is preparing the commissioning of terrorist acts from its territory or through its agents.

Such strikes would need to be limited to forestalling actual or imminent terrorist attacks.

Punitive air strikes or warning shots against a state are prohibited.

An invasion to remove Saddam Hussein could also not be easily justified with reference to the doctrine of humanitarian intervention.

That doctrine itself has been questioned by some legal analysts and governments in the
wake of the Kosovo campaign.

No-fly zones

However, it only permits international action that is strictly necessary to rescue a civilian population from imminent and overwhelming peril.

Since 1991, the US and UK have forcibly kept northern and southern Iraq free of Saddam's air-force to ensure that threatened Kurdish and Shiite minority populations will not be subjected to an attack by the Baghdad government.

The decision over the invasion of Iraq is one that will have
consequences that reach far beyond the Middle East

There does not at present seem to
exist an urgent humanitarian necessity to go beyond those steps.

Indeed, some may doubt whether the no-fly zones are even at present maintained and enforced for purely humanitarian reasons.

Finally, an invasion might be justified if it is undertaken to support the
people of Iraq themselves in a struggle to end decades of dictatorship.

This argument was deployed to some effect in the context of support
rendered to the United Front (sometimes called Northern Alliance) in overthrowing the Taleban government in Afghanistan.

However, the principal responsibility would first lie with the people of Iraq to disown the present regime and make unambiguously manifest the fact that the Hussein
government cannot conceivably claim to represent their state.

Overall, the decision over the invasion of Iraq is one that will have
consequences that reach far beyond the Middle East.

If a massive armed action is undertaken, it will challenge or change our understanding of the
role and relevance of international legal considerations in world politics
in the increasingly unipolar world.